Complex systems (CS) involve many elements that interact at different scales in time and space. The challenges in modeling CS led to the development of novel computational tools with applications in a wide range of scientific areas. The computational problems posed by CS exhibit intrinsic difficulties that are a major concern in Computational Complexity Theory. This Special Issue (SI) focused o...

Computational Complexity a k a Complexity Theory is a central eld of Com puter Science with a remarkable list of celebrated achievements as well as a very vibrant research activity The eld is concerned with the study of the intrinsic complexity of computational tasks and this study tend to aim at generality It focuses on natural computational resources and considers the e ect of limiting these ...

Computational complexity theory is the study of the minimal resources needed to solve computational problems. In particular, it aims to distinguish between those problems that possess efficient algorithms (the “easy” problems) and those that are inherently intractable (the “hard” problems). Thus computational complexity provides a foundation for most of modern cryptography, where the aim is to ...

We study the computational complexity of languages which have interactive proofs of logarithmic knowledge complexity. We show that all such languages can be recognized in BPPNP . Prior to this work, for languages with greater-than-zero knowledge complexity only trivial computational complexity bounds were known. In the course of our proof, we relate statistical knowledge complexity to perfect k...

We prove several results about the relationship between word complexity function of a subshift and set Turing degrees points subshift, which we call spectrum. Among other results, show that spectrum can be realized via linear if only it consists union finite number cones, exponential (i.e. positive entropy) contains cone, every either degree <tex-mat...

Existing project selection models do not consider the complexity of projects as a selection criterion, while their complexity may prolong the project duration and even result in its failure. In addition, existing models cannot formulate the aggregate complexity of the selected projects. The aggregated complexity is not always equal to summation of complexity of projects because of possible syne...